Typewriting machine



May 25,1926.

J. LINDBURG I'YPEWRITING MACHINE Fil ed Oct. 26, 1922 Patented May 25, 1926.

UNITED STATES I 1,586,094 PATIENT OFFICE.

. I, JOSEPH LINDBURG, OF BROOKLYN, NEW YORK, ASSIGNOR T UNDEBWOOD TYPE- WRITER. COMPANY, OF NEW YORK. N. Y., A CORPORATION or DELAWARE.

TYPEWBITING MACHINE.

Application filed October 26, 1922. Serial- No. 596,960.

The present invention relates to platens for typewriting machines, and more particularly to platens of the so-called noiseless class.

, It is Well known that if a'platen be soft,

. or if the type-stroke be slow, the noise of typewriting will be less than where there is a sharp type-stroke against ahard platen. Such so-called noiselessness, even where hardening of the platen with age does not take place, has heretofore been obtained at the sacrifice of quality in the printing, particularly as to the printing on the under sheets of manifolds.

Heretofore, also, in an effort to deaden the noise of typewriting, while maintaining the desirable hard-rubber platen-facing, the hard-rubber facing has been insulated from the platen-core by an interior sleeve or base of soft rubber or other sound-deadening and insulating material. This expedient, while effective in deadening the sound, has not always been. satisfactory, because the softer, interior rubber sleeve has lacked the rigidity necessary-to prevent indentation, by the type, of the harder rubber facing, due to severe and often repeated type-blows at the same points on the platen.

An object of the invention is the production of a platen,'which, in use, may be relatively noiseless, and which, nevertheless, will assure clearness of type-impressions through any desired manifolding of copy thereon, without being unduly susceptible to indentation by the type.

A further object of the invention is the provision of means whereby the usual core, of wood or other material, on which the facing-sleeve is fitted, may be deadened, as respects sound-vibrations therein, in a simple and inexpensive manner, and without impairment of the desirable qualities of such a core as a base for the facing-sleeve.

A feature of the invention is the sub-division of the core, into sections or segments, by slots extending longitudinally of the platen, which slots, when the core is of wood, break the grain thereof, and which, in any event, intercept and break the sound-waves generated within the core. In the preferred form of the invention, these slots have a filling of soft rubber or other sound-deadening material.

Also, in the preferred form of the invention, another feature thereof is direction of the slots into the core tangentially to a circle or curve between the axis of the platen and the periphery thereof; whereby the fillings of soft rubber or other material for the slots serve as sound-deadening and insulating bases for the several core sections or segments formed by the slots.

Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure '1 is a view in cross-section through the platen; a type being shown in position at the printing-point.

Figure 2 isa perspective view of the platen; the facing-sleeve being broken away to show the core and one of the rubber in serts, and the head of the platen being set out away from the core for a clearer illustration of the parts.

On a core 10, of wood 01' other suitable material, is fitted the usual hard-rubber facing-sleeve 11. Screwed to the ends of the core are heads 12, having bosses 13 thereon which serve as bearings for the platen on its axle 14. A type 15 is shown at the printing-point.

Disposed around the core and directed from the periphery thereof, toward the hollow interior thereof, are slots 16. These slots are preferably directed tangentially to an imaginary circle concentric with the axis of the platen. In each slot 16 is placed an insert 18 of rubber or other sound-deadening material.

The inserts 18 may conveniently be built of rubber bands which are stretched for insertion into the slots, and which, when rerender the core segments or sections slightly yieldable under type-strokes, and, in this way, further enhance the sound-deadening quality of the core.

Whether the slots 'be directed tangentially or radially, they serve to break the grain of laten for a typewriting machine,

comprising a facing-sleeve of hard rubberor other suitable material, and a relatively rigid core slotted throughout its entire length from the periphery thereof tangentially inward, at intervals therearound.

2. A platen for a typewritin machine, comprislng a facing-sleeve of har rubber or other suitable material, and a core, of Woodor similar material, having fine narrow slots extending inward from the periphery thereof and from end to end, at intervals therearound. a 3. A platen for a typewriting :m-achine, comprising a facing-sleeve of hard rubber or other suitable. material, and a core on which the sleeve is fitted; the core having slots therein and therearound directed tangentially to a curve between the axis of the platen and the periphery thereof.

4. A laten for a typewriting machine, comprising a. facing-sleeve of hard rubber comprislng a facing-sleeve of hard rubber or other suitable material, a core on which the facing-sleeve is set; the core being slotted throughout the entire len h thereof, at intervals therearound; an inserts of soft rubber or other sounddeadening material in the slots, in direct contact with the facingsleeve.

6. A platen for a typewriting machine, comprising a facing-sleeve of hard rubber or other. suitable material, a core on which the facing-sleeve is set the core being slotted longitudinally thereo at intervals therearound; and inserts built of elastic bands placed in the slots in stretched condition, and thereafter relaxed to cause the same to fill the slots from wall to wall thereof.

7. A platen for a typewriting machine, comprisin a facing-sleeve, a core directly engaged t erein, said core having a plurality of tangentially-disposed narrow slots extending its entire length presenting yieldable members therebetween, and a resilient filler in each slot.

JOSEPH LINDBURG. 

